Does the number of elements in the Bucket array change during the operation of the HashMap structure?

In Java, the HashMap structure uses an array of buckets, each of which is a linked list or a tree (in newer versions) to store elements with the same hash.

The number of buckets (array size) in a HashMap can change during operation, but not dynamically during the addition of elements. When a certain load factor threshold is reached, a resize occurs: a new, larger array of buckets is created, and all elements are redistributed across the new buckets.

Thus, the number of buckets within the HashMap structure only changes during a resize, not with each element addition.

Key points:

• Initially, the bucket array has a fixed size.
• When the load factor threshold is exceeded, the array size increases and redistribution occurs.
• Inside each bucket, the number of elements can change dynamically (lists or trees).